The invention relates to friction clutches in general, and more particularly to improvements in methods of and in means for facilitating attachment of friction clutches to torque-transmitting and/or torque-receiving parts, e.g., in the power train between the engine and the wheels of a motor vehicle.
A friction clutch for use in motor vehicles normally comprises a cover or housing which carries a diaphragm spring serving to bias a pressure plate toward a clutch plate. The clutch plate is thereby clamped against and can receive torque from a flywheel which also rotates the cover. The flywheel can be mounted on the output shaft of the engine in a motor vehicle, and the clutch plate can be mounted on the input shaft of a variable-speed transmission so that the input shaft receives torque from the output shaft when the engine is on and the clutch is engaged. The pressure plate rotates with the flywheel and with the cover because it is secured to the cover by a set of leaf springs which enable the pressure plate to move axially of but prevent the pressure plate from turning relative to the cover and flywheel.
It is customary to pack the unit including the cover, pressure plate, leaf springs and diaphragm spring independently of the clutch plate. When such clutches are to be installed in motor vehicles, clutch plates are delivered to the production line on a first set of pallets whereas the units including the covers, pressure plates and diaphragm springs are delivered to the production line on a separate second set of pallets. It is then necessary to prepare the two units of each clutch for actual installation in a motor vehicle in that the units are unpacked and the clutch plate is centered relative to the pressure plate and other parts of the clutch. This contributes to the cost of the clutch and of installation of the clutch in a motor vehicle.